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D2 - Engine Bay Everything under the bonnet

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  #1  
Old 21st December 2021, 07:33 PM
Audifan Audifan is offline
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Default S8 cylinder head

I don't have everything I need yet for my big job that I need to do but I want to at least start. Any tips on removing the cylinder heads and do I need any special tools?
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2001 S8 (build date March 16th 2001) Brilliant black with black interior and Recaro seats.
Mods prior to my ownership: 01E 6 speed, carbon fiber trim, bi-xenon, aftermarket muffler with x-pipe, tinted windows, non-tip steering wheel, Spal electric fan.

My mods: LED interior lights, D3 ignition coils, new window tint, tip steering wheel with new S8 emblem
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Old 21st December 2021, 09:16 PM
MikkiJayne MikkiJayne is offline
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A long M10 spline / triple square. I think thats really it.

Soak the exhaust manifold nuts in something for a while. Chances are the two long ones which go through the manifold will take the studs out with them since you can only get penetrant to them with the engine out and on its side.

Bolt order is the same as you'd expect for a 4 cylinder.

Engine in or out?
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Old 21st December 2021, 09:52 PM
Audifan Audifan is offline
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How long M10 triple square? Do I need timing belt service tools in order to remove the cylinder heads?

The engine is staying in the car.

Any other tips?
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2001 S8 (build date March 16th 2001) Brilliant black with black interior and Recaro seats.
Mods prior to my ownership: 01E 6 speed, carbon fiber trim, bi-xenon, aftermarket muffler with x-pipe, tinted windows, non-tip steering wheel, Spal electric fan.

My mods: LED interior lights, D3 ignition coils, new window tint, tip steering wheel with new S8 emblem
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Old 22nd December 2021, 07:08 AM
MikkiJayne MikkiJayne is offline
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Quote:
Originally Posted by Audifan View Post
Any other tips?
Take the engine out

You'll need timing tools to put the heads back on. Taking them off doesn't matter.

The SAI rubbish will need removing from the back of the heads, which isn't fun. You'll also need to disconnect the coolant link pipe from the heads, but that will be difficult to remove with the engine in place.

Coolant pipe along the side of the bank 1 head - thats connected to the link pipe with a hose and some spring clips. Possible to get to that with the SAI stuff removed.

Leave the exhaust manifolds on the heads and disconnect the downpipes. Remove the manifolds on the bench if needed.

I have a 100mm triple square.

Can't think of anything else.
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Old 22nd December 2021, 07:17 PM
Audifan Audifan is offline
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The engine is staying in the car as I don't have required items to take it out and also don't have a engine stand.

What is SAI?
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2001 S8 (build date March 16th 2001) Brilliant black with black interior and Recaro seats.
Mods prior to my ownership: 01E 6 speed, carbon fiber trim, bi-xenon, aftermarket muffler with x-pipe, tinted windows, non-tip steering wheel, Spal electric fan.

My mods: LED interior lights, D3 ignition coils, new window tint, tip steering wheel with new S8 emblem
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  #6  
Old 22nd December 2021, 07:39 PM
MikkiJayne MikkiJayne is offline
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Secondary Air Injection - the shiny pods on the back of each head, connected by a piece of stainless tube.
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  #7  
Old 26th December 2021, 07:10 PM
Audifan Audifan is offline
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Ah ok.

Just thinking out loud. Can the valve springs be replaced without removing the cylinder heads if you don't have a air compressor to use?
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2001 S8 (build date March 16th 2001) Brilliant black with black interior and Recaro seats.
Mods prior to my ownership: 01E 6 speed, carbon fiber trim, bi-xenon, aftermarket muffler with x-pipe, tinted windows, non-tip steering wheel, Spal electric fan.

My mods: LED interior lights, D3 ignition coils, new window tint, tip steering wheel with new S8 emblem
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  #8  
Old 28th December 2021, 08:44 AM
MikkiJayne MikkiJayne is offline
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One head no, the other head maybe. The roller rockers need to come out to get a spring compressor in there, and they run on a shaft which goes the whole length of the head. On one side those shafts come out forwards, but on the other they would hit the firewall.

I don't know how you would compress the springs with the heads on. I know on some engines it can be done, but I've never tried that on any engine tbh so couldn't really comment on that aspect of it.
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  #9  
Old 28th December 2021, 04:23 PM
Audifan Audifan is offline
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Ah, ok. The cylinder heads are coming off.

Next questions. How do I get the engine to TDC and how do I know it's at TDC? I'm guessing that I need to paint mark the timing before I remove the cylinder heads?

After I install the new valve springs and reinstall the cylinder heads, I will be installing new timing belt parts. I just want to make sure I do everything right before I start.
__________________
2001 S8 (build date March 16th 2001) Brilliant black with black interior and Recaro seats.
Mods prior to my ownership: 01E 6 speed, carbon fiber trim, bi-xenon, aftermarket muffler with x-pipe, tinted windows, non-tip steering wheel, Spal electric fan.

My mods: LED interior lights, D3 ignition coils, new window tint, tip steering wheel with new S8 emblem
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  #10  
Old 28th December 2021, 07:26 PM
MikkiJayne MikkiJayne is offline
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You need the locking tool set. There is a pin which goes in the block on the left hand side and locks the crank in TDC, and a bar which locks the two cams together also at TDC. You'll need to that to refit the belt afterwards anyway.

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